Small cleanup and formatting

8 files changed, 62 insertions, 347 deletions

diff --git a/run b/run
index c0efa1b..b181689 100755
--- a/run
+++ b/run
@@ -105,6 +105,14 @@ make_build() {
 	cp ./src/bootloader/grub.cfg ./iso/boot/grub/
 	grub-mkrescue -o ./build/melvix.iso ./iso/
 
+	# Check ISO
+	if grub-file --is-x86-multiboot2 ./build/kernel.bin; then
+		echo "Multiboot confirmed"
+	else
+		echo "Kernel is corrupted!"
+		exit 1
+	fi
+
 	# Create disk image
 	make_genext2fs
 	mkdir ./mnt/
diff --git a/src/kernel/boot.asm b/src/kernel/boot.asm
index d15bce4..363f76a 100644
--- a/src/kernel/boot.asm
+++ b/src/kernel/boot.asm
@@ -1,85 +1,52 @@
 section .multiboot
-    header_start:
-        dd 0xe85250d6
-        dd 0
-        dd header_end - header_start
-        dd 0x100000000 - (0xe85250d6 + 0 + (header_end - header_start))
-
-        ; Information tag
-        align 8
-        dw 1
-        dw 1
-        dd 24
-        dd 2 ; bootloader name
-        dd 4 ; meminfo
-        dd 6 ; mmap
-        dd 13 ; smbios
-
-        ; Empty tag
-        align 8
-        dw 0
-        dw 0
-        dd 8
-    header_end:
+	header_start:
+		dd 0xe85250d6
+		dd 0
+		dd header_end - header_start
+		dd 0x100000000 - (0xe85250d6 + 0 + (header_end - header_start))
+
+		; Information tag
+		align 8
+		dw 1
+		dw 1
+		dd 24
+		dd 2 ; bootloader name
+		dd 4 ; meminfo
+		dd 6 ; mmap
+		dd 13 ; smbios
+
+		; Empty tag
+		align 8
+		dw 0
+		dw 0
+		dd 8
+	header_end:
 
 section .start_section
-    dd _start
+	dd _start
 
 ; Initialize stack
 section .bss
-    align 16
-    global STACK_BOTTOM
-    global STACK_TOP
+	align 16
+	global STACK_BOTTOM
+	global STACK_TOP
 
-    STACK_BOTTOM:
-        resb 0x4000
-    STACK_TOP:
+	STACK_BOTTOM:
+		resb 0x4000
+	STACK_TOP:
 
 section .text
-    global _start
-    extern kernel_main
-    _start:
-        mov esp, STACK_TOP
-        push ebx
-        push eax
-        cli
-        call kernel_main
-        cli
-        jmp $
-
-    global jump_userspace
-    jump_userspace:
-        cli
-        push ebp
-        mov ebp, esp
-        mov edx, dword [esp + 0xC]
-        mov esp, edx
-        push 0xABCDEF
-
-        mov ax, 0x23
-        mov ds, ax
-        mov es, ax
-        mov fs, ax
-        mov gs, ax
-
-        mov eax, esp
-        push 0x23
-        push eax
-        pushf
-
-        ; Enable interrupts
-        pop eax
-        or eax, 0x200
-        push eax
-
-        push 0x1B
-        push dword [ebp + 8]
-        iret
-
-        pop ebp
-        ret
+	global _start
+	extern kernel_main
+	_start:
+		mov esp, STACK_TOP
+		push ebx
+		push eax
+		cli
+		call kernel_main
+		; cli
+		jmp $
 
 section .end_section
-    global ASM_KERNEL_END
-    ASM_KERNEL_END:
-        ; Kernel size detection
\ No newline at end of file
+	global ASM_KERNEL_END
+	ASM_KERNEL_END:
\ No newline at end of file
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index 441f188..b0850b7 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -11,7 +11,6 @@
 #include <kernel/syscall/syscall.h>
 #include <kernel/pci/pci.h>
 #include <kernel/net/network.h>
-#include <kernel/tasks/task.h>
 #include <kernel/fs/load.h>
 #include <kernel/fs/elf.h>
 #include <kernel/lib/stdio.h>
@@ -66,18 +65,9 @@ void kernel_main(uint32_t magic, uint32_t multiboot_address)
 
 	elf_load("/bin/user");
 
-	// tasking_install();
-
 #ifdef INSTALL_MELVIX
 	panic("Installation isn't supported right now!");
 #endif
 
-	// load_elf((char *)userspace);
-
-	// syscalls_install();
-	// exec(userspace);
-
-	// panic("This should NOT happen!");
-
 	// asm ("div %0" :: "r"(0)); // Exception testing x/0
 }
\ No newline at end of file
diff --git a/src/kernel/linker.ld b/src/kernel/linker.ld
index ff04c17..eda4b85 100644
--- a/src/kernel/linker.ld
+++ b/src/kernel/linker.ld
@@ -1,28 +1,34 @@
 ENTRY(_start)
 
-SECTIONS {
+SECTIONS
+{
 	. = 1M;
 
-	.text BLOCK(4K) : ALIGN(4K) {
+	.text BLOCK(4K) : ALIGN(4K)
+	{
 		*(.multiboot)
 		*(.start_section)
 		*(.text)
 	}
 
-	.rodata BLOCK(4K) : ALIGN(4K) {
+	.rodata BLOCK(4K) : ALIGN(4K)
+	{
 		*(.rodata)
 	}
 
-	.data BLOCK(4K) : ALIGN(4K) {
+	.data BLOCK(4K) : ALIGN(4K)
+	{
 		*(.data)
 	}
 
-	.bss BLOCK(4K) : ALIGN(4K) {
-		*(COMMON)
+	.bss BLOCK(4K) : ALIGN(4K)
+	{
+		*(.COMMON)
 		*(.bss)
 	}
 
-	.end_section BLOCK(4K) : ALIGN(4K) {
+	.end_section BLOCK(4K) : ALIGN(4K)
+	{
 		*(.end_section)
 	}
 }
\ No newline at end of file
diff --git a/src/kernel/tasks/process.asm b/src/kernel/tasks/process.asm
deleted file mode 100644
index a46ac3d..0000000
--- a/src/kernel/tasks/process.asm
+++ /dev/null
@@ -1,48 +0,0 @@
-[GLOBAL read_eip]
-read_eip:
-    pop eax
-    jmp eax
-
-[GLOBAL copy_page_physical]
-copy_page_physical:
-    push ebx
-    pushf
-
-    cli
-
-    mov ebx, [esp+12]
-    mov ecx, [esp+16]
-
-    mov edx, cr0
-    and edx, 0x7fffffff
-    mov cr0, edx
-
-    mov edx, 1024
-
-.loop:
-    mov eax, [ebx]
-    mov [ecx], eax
-    add ebx, 4
-    add ecx, 4
-    dec edx
-    jnz .loop
-
-    mov edx, cr0
-    or  edx, 0x80000000
-    mov cr0, edx
-
-    popf
-    pop ebx
-    ret
-
-[GLOBAL perform_task_switch]
-perform_task_switch:
-     cli
-     mov ecx, [esp+4]
-     mov eax, [esp+8]
-     mov ebp, [esp+12]
-     mov esp, [esp+16]
-     mov cr3, eax
-     mov eax, 0x12345
-     sti
-     jmp ecx
\ No newline at end of file
diff --git a/src/kernel/tasks/task.c b/src/kernel/tasks/task.c
deleted file mode 100644
index 036c5d4..0000000
--- a/src/kernel/tasks/task.c
+++ /dev/null
@@ -1,177 +0,0 @@
-#include <kernel/memory/paging.h>
-#include <kernel/tasks/task.h>
-#include <kernel/memory/alloc.h>
-#include <kernel/lib/lib.h>
-#include <kernel/io/io.h>
-#include <kernel/gdt/gdt.h>
-#include <kernel/system.h>
-
-task_t *current_task;
-task_t *ready_queue;
-
-extern uint32_t read_eip();
-
-uint32_t next_pid = 1;
-
-void tasking_install()
-{
-	cli();
-	move_stack((void *)0xE0000000, 0x2000);
-
-	current_task = ready_queue = (task_t *)kmalloc(sizeof(task_t));
-	current_task->id = (int)next_pid++;
-	current_task->esp = 0;
-	current_task->ebp = 0;
-	current_task->eip = 0;
-	current_task->page_directory = current_page_directory;
-	current_task->next = 0;
-	current_task->kernel_stack = kmalloc(KERNEL_STACK_SIZE);
-
-	vga_log("Installed Tasking");
-	sti();
-}
-
-void move_stack(void *new_stack_start, uint32_t size)
-{
-	for (uint32_t i = (uint32_t)new_stack_start; i >= ((uint32_t)new_stack_start - size);
-	     i -= 0x1000) {
-		// paging_alloc_frame(paging_get_page(i, 1, current_page_directory), 0, 1);
-	}
-
-	uint32_t pd_addr;
-	asm volatile("mov %%cr3, %0" : "=r"(pd_addr));
-	asm volatile("mov %0, %%cr3" : : "r"(pd_addr));
-
-	uint32_t old_stack_pointer;
-	asm volatile("mov %%esp, %0" : "=r"(old_stack_pointer));
-	uint32_t old_base_pointer;
-	asm volatile("mov %%ebp, %0" : "=r"(old_base_pointer));
-
-	uint32_t offset = (uint32_t)new_stack_start - initial_esp;
-
-	uint32_t new_stack_pointer = old_stack_pointer + offset;
-	uint32_t new_base_pointer = old_base_pointer + offset;
-
-	memcpy((void *)new_stack_pointer, (void *)old_stack_pointer,
-	       initial_esp - old_stack_pointer);
-
-	for (uint32_t i = (uint32_t)new_stack_start; i > (uint32_t)new_stack_start - size; i -= 4) {
-		uint32_t tmp = *(uint32_t *)i;
-		if ((old_stack_pointer < tmp) && (tmp < initial_esp)) {
-			tmp = tmp + offset;
-			uint32_t *tmp2 = (uint32_t *)i;
-			*tmp2 = tmp;
-		}
-	}
-
-	asm volatile("mov %0, %%esp" : : "r"(new_stack_pointer));
-	asm volatile("mov %0, %%ebp" : : "r"(new_base_pointer));
-}
-
-extern void perform_task_switch(uint32_t, uint32_t, uint32_t, uint32_t);
-
-void switch_task()
-{
-	if (!current_task)
-		return;
-
-	uint32_t esp, ebp, eip;
-	asm volatile("mov %%esp, %0" : "=r"(esp));
-	asm volatile("mov %%ebp, %0" : "=r"(ebp));
-
-	eip = read_eip();
-
-	if (eip == 0x12345)
-		return;
-
-	current_task->eip = eip;
-	current_task->esp = esp;
-	current_task->ebp = ebp;
-
-	current_task = current_task->next;
-	if (!current_task)
-		current_task = ready_queue;
-
-	eip = current_task->eip;
-	esp = current_task->esp;
-	ebp = current_task->ebp;
-
-	current_page_directory = current_task->page_directory;
-
-	set_kernel_stack((uintptr_t)(current_task->kernel_stack + KERNEL_STACK_SIZE));
-
-	paging_switch_directory((int)current_page_directory);
-	perform_task_switch(eip, (uint32_t)current_page_directory, ebp, esp);
-}
-
-int fork()
-{
-	cli();
-
-	task_t *parent_task = (task_t *)current_task;
-
-	uint32_t *directory = 0; //paging_clone_directory(current_page_directory);
-
-	task_t *new_task = (task_t *)kmalloc(sizeof(task_t));
-	new_task->id = (int)next_pid++;
-	new_task->esp = new_task->ebp = 0;
-	new_task->eip = 0;
-	new_task->page_directory = directory;
-	current_task->kernel_stack = kmalloc(KERNEL_STACK_SIZE);
-	new_task->next = 0;
-
-	task_t *tmp_task = (task_t *)ready_queue;
-	while (tmp_task->next)
-		tmp_task = tmp_task->next;
-	tmp_task->next = new_task;
-
-	uint32_t eip = read_eip();
-
-	if (current_task == parent_task) {
-		uint32_t esp;
-		asm volatile("mov %%esp, %0" : "=r"(esp));
-		uint32_t ebp;
-		asm volatile("mov %%ebp, %0" : "=r"(ebp));
-		new_task->esp = esp;
-		new_task->ebp = ebp;
-		new_task->eip = eip;
-		sti();
-
-		return new_task->id;
-	} else {
-		return 0;
-	}
-}
-
-int getpid()
-{
-	return current_task->id;
-}
-
-void exec(uint32_t binary)
-{
-	set_kernel_stack((uintptr_t)(current_task->kernel_stack + KERNEL_STACK_SIZE));
-
-	info("Switching to user mode...");
-
-	asm volatile("\
-      cli; \
-      mov $0x23, %%ax; \
-      mov %%ax, %%ds; \
-      mov %%ax, %%es; \
-      mov %%ax, %%fs; \
-      mov %%ax, %%gs; \
-      mov %%esp, %%eax; \
-      pushl $0x23; \
-      pushl %%esp; \
-      pushf; \
-      pushl $0x1B; \
-      push $1f; \
-      iret; \
-      1: \
-      "
-		     :
-		     : "r"(binary));
-
-	// syscall_write("test");
-}
\ No newline at end of file
diff --git a/src/kernel/tasks/task.h b/src/kernel/tasks/task.h
deleted file mode 100644
index 8652e44..0000000
--- a/src/kernel/tasks/task.h
+++ /dev/null
@@ -1,30 +0,0 @@
-#ifndef MELVIX_TASK_H
-#define MELVIX_TASK_H
-
-#include <stdint.h>
-#include <kernel/memory/paging.h>
-
-#define KERNEL_STACK_SIZE 2048
-
-typedef struct task {
-	int id;
-	uint32_t esp, ebp;
-	uint32_t eip;
-	uint32_t *page_directory;
-	uint32_t *kernel_stack;
-	struct task *next;
-} task_t;
-
-void tasking_install();
-
-void switch_task();
-
-int fork();
-
-void move_stack(void *new_stack_start, uint32_t size);
-
-int getpid();
-
-void exec(uint32_t binary);
-
-#endif
\ No newline at end of file
diff --git a/src/kernel/timer/timer.c b/src/kernel/timer/timer.c
index 1bbf41b..f1a296a 100644
--- a/src/kernel/timer/timer.c
+++ b/src/kernel/timer/timer.c
@@ -1,7 +1,6 @@
 #include <kernel/interrupts/interrupts.h>
 #include <kernel/io/io.h>
 #include <kernel/system.h>
-#include <kernel/tasks/task.h>
 
 unsigned long timer_ticks = 0;